I do most of my spinning using a spindle, and since I started with a high-whorl tool, they're still what I use. As far as resources for learning to use one, hunt down writings by Abby Franquemont on Ravelry, on her blog, or her book and video. She has very good information for becoming more efficient with the tool. Even better is spending time with other spindle spinners, and watching how they coordinate their hands, and how they think about the process of spinning. As far as really learning, the best way is to spin for at least 15 minutes each day...it's really something your body has to learn to do once you get the basic concepts down intellectually, a lot like riding a bike. Eventually, it all just "clicks" and you'll think "Oh...this is how it works."